Igniter for internal-combustion motors.



JOHNSTON.

IGNITER FOR INTERNAL COMBUSTION MOTORS.

APPLICATION FILED SEPT. 21, 1907.

UNITED STATES PATENT OFFICE.

I HOWARD A. JOHNSTON, OF TORONTO, ONTARIO. CANADA.

IGNITER FOR INTERNAL-COMBUSTION MOTORS.

Specification of Letters Patent.

Patented Dec. *7, 1909.

Application filed. September 27, 1907. Serial N0. 394,869.

To all whom it may concern:

Be it known that I, HOWARD ADDISON JOIINS'lON, of the city of Toronto,in the Province of Ontario, Canada, have invented certain new and usefulImprovements in a workable spark plug for heavy oils I have thereforefound it necessary to arrange itso that a small portion of the oil isvaporized by electrically 'enerated heat and the vapor ignited by an eectric spark. I have accomplished this result by so constructing theelectrodes of the plug that a portion of the spray of oil contacts withelectrode surfaces so located and constructed that the oil caughtthereon is collected at the spark gap and vaporized by the heat of a sark in passing from electrode to electrode, y heat due to electricalresistance or byboth, and

the vapor ignited by the spark.

The drawing shows a side elevation, partly in section, of my igniter.

A 1s a sparking lug, which is preferably of the soot proo type. In thistype of plug a porcelain petticoat B surrounds the central electrode bThe other electrode D isl connected with the metal part E of the 1) ug.

The object of my igniter being to vaporize a small quantity of oil forsubsequent ignition by the spark, I make the end of one of theelectrodes of comparatively fine wire, and so arrange them that there ispresented at the spark gap a surface, or surfaces, adapted to collectbetween them a certain amount of any fluid which may be sprayed yagainstthe igniter, and this fluid is vaporized at the time of passingof the spark, partly by the heat of the spark and partly also in allprobability by the heat due to the electrical resistance of thecomparatively 50= the drawing .is shown on a large scale to betfineelectrode. It should be noted here that ter illustrate the arts.

I have found t at better results tained by are obproviding special meansfor directing against the electrodes a part of any fluid sp rayed in thedirection of the igniter.

It is also preferable that the directing means should also effect aconcentration of the spray. For this purpose I provide a receiver F,which forms part of one of the electrodes and insures the accumulationof a sufficient quantity of fluid adjacent to the spark gap to furnishsufiicient vapor for lgnition purposes. To retain the liquid adjacentthe spark gap, the receiveris so shaped as to form a cup I below thespark gap and is preferably closed at its inner end so that any sprayedliquid striking within the receiver flows down into the bottom of thecup I.

The outer electrode D is bent around and turned parallel to the cup fora short distance adjacent to the s ark gap and is formed of a fine wire.wing to the cup there is necessarily a comparatively large accumulationof fluid at the spark gap, and when a spark passes so much 011 isvaporized that a comparatively large flame is formed which isexceedingly efficient in igniting a spray of liquid fuel. If so much oilaccumulates in the cup and at the s ark gap that the spark cannot breakthroug a discharge will take place .over the surface of the fluid to thenearest part of the cup to the point of the electrode D. 7

An igniter such as described forms an excellent starting igniter forengines using crude oil as fuel as it will ignite the spray withcertainty and does not become clogged. It will also be seen that as thewire electrode extends above the rim of the cup within sparking distanceof the rim, in no case can the spark gap be completely insulated withoil as the maximum possible oil level is below the highest possibleposition of the spark gap.

WVhat I claim as my invention is:

1. An. igniter for internal combustion motors comprising a sparking plugprovided with suitable electrodes, one electrode being shaped to form acup, andpthe other shaped as a wire extending from without the cupwithin sparking distance of the rim of the cup. i

2. An igniter for internal combustion motors comprising a sparking plugipro vided with suitable electrodes, oneelectrode being shaped to form acup, and the other shaped as a wire enterin the cup fr in without andextending within sparkin' distance of the cup at any point of theiroverlap.

3. An igniter for internal combustion motors com-prising a sparking plugprovided with electrodes suitably shaped to form between them a sparkgap and a cu below the spark gap shaped to give a maximum possible fluidlevel slightl below the spark gap whereby a supply 0 liquid fuel may beheld at the spark gap which cannot rise above and insulate the sparkgap.

4. An igniter for internal combustion motors, comprising a sparking plugprovided with a suitable electrode; and a cup formed as part of anotherelectrode formin a spark gap with the first electrode, adapted toconcentrate a spray of fuel upon the s ark gap, and cupped below thespark gap, t e first electrode being formed of comparatively fine wire.

5-. igniter for internal combustion motors, 'coinprisin a sparking plugprovided with a suita le electrode; and a cup formed as part of anotherelectrode and located at the spark gap, one of the electrodes beingformed of'com aratively fine wire. Toronto, Ont., 16t September, 190?:

HOWARD A. JOHNSTON. Signed in presence of- J. EDW, MAYBEE,

F. W. McKnNmuoK.

